Various electrical codes require in-conduit wiring for runs emanating from power boxes and terminating at termination points, such as receptacles, in or outside of a building. Commonly, the conduits are filled to about 80% capacity in new construction. These conduits are often installed before the interior of new construction is completed and may also be in place in existing construction—both interior and exterior uses. Not all wiring is used initially, as the intent is to have excess capacity available when needed without the costly need to run additional conduit. Because of the high capacity in a conduit, working in an existing conduit may be space limited.
As a part of the electrical building code, conduit runs include devices called conduit outlet bodies, or condulets, typically placed every 100 feet or less and/or after every third 90 degree bend. These condulets provide access to the embedded wiring and serve as junction points for internal wiring and afford access to embedded wiring if needed. Condulets have removable cover plates and, when the cover plate is removed, the internal wiring is accessible to an electrician, such as to obtain access to wiring for splicing purposes. However, because the wiring remains embedded in the conduit and the available space in the conduit for rewiring may be limited, new wiring to a different portion of the building typically needs to be extended from one of the available ends of the conduit points of connection at either the end near the power box or the distal end, and not from the condulet. In some circumstances, the electrical code requires wiring to be in conduit. Because of the obligation to have wiring in conduit, additional wiring requires laying new conduit from the point of connection and has expense associated with any system down-time, labor, and materials of the installing the new conduit.